In recent years, a touch panel has been popularly used, as an input apparatus of an operation unit for receiving an input operation by an operator, in mobile terminals such as mobile phones and gaming machines; information equipment such as calculators and ticket vending machines; home electric appliances such as microwaves, TV sets and lighting equipment; industrial equipment (FA equipment) and the like. The touch panel is generally configured by a touch sensor and a display panel such as an LCD (Liquid Crystal Display) panel or an EL (Electroluminescence Display) panel having the touch sensor disposed thereon.
There are known a variety of types of the touch sensors, such as a resistive film type, a capacitive type, an optical type and the like. However, the touch sensors of these types receives a touch input (the input operation) by a pressing means such as a finger or a stylus pen and, unlike push-button switches, the touch sensors themselves are not physically displaced when being touched. Therefore, the operator may not be able to obtain feedback to the input operation, which causes a concern that an operator is likely to perform erroneous inputs.
In order to solve such a problem, the applicant has developed a touch panel that detects an input applying a predetermined pressing load on the touch sensor and vibrates the touch sensor in response thereto such that a tactile sensation is provided to the operator (for example, see Patent Document 1).